Taper tool for tapering fiber conduit or pipe in the field



May 22. 1956 R. A. THOMPSON TAPER TOOL F'OR TAPERING FIBER CONDUIT OR PIPE IN THE FIELD 2 Sheets-Sheet 1 Filed Sept. 29, 1953 May 22, 1956 R. A. THOMPSON 2,746,497

TAPER TOOL POR 'PAPERINO FIBER OONOUIT OR PIPE 1N THE FIELD Filed Sept. 29, 1953 2 Sheets-Sheet 2 1N VEN TOR.

Hwy/j TTOIHVEY United States Patent O 1 claims. (ci. 1445-205) h This invention relates toa tapering tool for cuttinga .taper on the end of a cylindricalpipe.

The disclosure vherein has heenshown but 'not s pecilically claimed in the abandoned application of Joseph G. Atwood, Serial No. 290,529, led May 28,7 1952, and

assigned to the assignee ofthe present invention.

Numerous tapering tools .have heretofore been` devised but Ithey have not 4gained widespread acceptance because of ,their generally complicated structure, in CQnvenient mode of operation, 'high cost of manufacture and inability to `cut .a smooth, `regular taper.

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Shaft 2 has an enlarged portion in diameter extending from pipe 1 and having at one end`a lead screw 1 2. A tapered sleeve 13 is journaled on lead screw 12 of shaft 2. One of the ends of sleeve 1 3 is in bearing relation `with face 64IV of collar 5a of the mandrel assembly. Although the'enlarged portion of the shaft acts as a retaining means for limitingmovement ofthe collar 5a in one direction o n the shaft, it will be obvious to those skilled in the art, that the portion 12 may be of vthe same diameter as the shaft 2 on which'. event the sleeve acts as a retaining means for preventing the collar 5a from moving outwardly of the liber pipe or away from its mating collar 5. Sleeve 13 is retained` against sliding movement in one direction by a snap ring 18 circunii jacent to and disposed in an annular groove 19 in shaft 2 near its outer en d. It will be seen in Fig 1 that the axis of the outer periphery of sleeve 13 is angularly disposed in relation to the longitudinal axis of shaft 2.

J AccordinglyQit is an object of this iriventiorrto proyid'e .a taper cutting tool having. a simplied structure with a minimum number 'of parts anda ,facile mode of operation. l

Another object of this invention ,is to provide a mandrel which `can be inserted interiorly of a ,pipe .and rapidly locked into .position for .beginning the taper cutting operation.

`A further object of this yinvention is to provide a feedfing mechanism which .causes a uniform taper to be .cut

Fig. 2 is an end `View in section taken von the ,f1 ine 2-2 of Pig. '1. Y

Fig. 3 is a side viewof the Vhub lshowing the latching lmechanism.

Fig. 4 is a Ytop yiew showing the locking plate and screw feedl engaging mechanism.

Fig. 5 lisa vfragmentary .side view, .in section, shuwiug y aualternativeform of ylocking mechanism.

Eig. 6 is `an .end -view of rembodiment shown inl-Tig. 5. v4Fig. l illustrates .the -novel 1taper cutting -tool `inserted within. n lbertubel. Illiemandreljportion.Ofithe .cutting device ,comprises a -shaft Y2 `having its axis coincident iwith thelongitudinal axisof. theber pipe 51. Atoneendof :shaft .2 andthreadedly-engaged'with;p0rtion 3 saco-llar .5. longitudinally` along shaft 2 is another-collar '5a which .has a centrally -located bore 9 vjournaledfon shaft i2. .Collars 5 and 5a aregsubstantiallysimilar :and each rhas 1` a .ange 16 on ,its outer iface. QA yrubber .or .resilient yring .7 bears against eachliange vof collars "5 and l5a. Thelouterzperiphery of ring 7 is inconcentric relation-to ,itheiinterior wall'of'pipeil. :A 'fhollowcylinderYS ,is dislposedlbetweenandibears againstthe rubber rings 7. A trotter-pin fllthroughtthe threaded end portion 3 of shaft -2facts as .airetain'erlto retain the` entire mandrel assembly llatchiug plate S2 is in the .position shown in Fig. 3, one

he taper ultimately cut upon the end of pipe 1 will conform to the same angle. The outer wall of sleeve `1 3 has a keyway slot 14 cut therein extending from one end longitudinally a distance substantially coextensiue with the length of the lead screw 12 of shaft 2.

A hub 32 having a smooth bore 32a `is revolvably c arried by the outer 'periphery of sleeve 13. To impel lthe hub 32 longitudinally along the sleeve 13 during a taper cutting operation, a shoe 3'7 disposed in slot 14 land having a threaded face 37a is provided. Shoe 37 hasja shank portion 38 radially disposed `relative to ,the shaft 2 and extending througha round whole' 36 in hub 3 2.` A lifting lever 4t) pivotallyy carries Vshoe 37 on pin 4 1 in shank portion 38 off shoe 37.y The threaded face 37a A of the shoe 37 `is normally biased in to threaded .engagement with lead screw l2 on shaft 2 by a spriugfl which is disposed in a recess 46 in hub 32.v This spring acts upon the end of lifting ylever 40.

Axial alignment o f `'conlpression spring 4 4 is maintained by interpos'ing, it between two anchoring p rotuberance s, ,onebeing a .pin 45 and the .other `a .protuberance 43 on lever 40. The force tending to fbias tl:ie sl 1oe 37 inwardly v toward the axis of shaft 2 and against lead s crew 1 2 vis produced by 4the action of springf44 urging Vthe lever {il} about `a fulcrumor pivot 42.

A latchng meclflanisrn is .provided .for lretracting vshoe 37 -from .threaded engagement with lead screw 12. This mechanism, which may `be best seen from Figs. Zand 3,

comprises a .latchingplate 5 2 havingone of its ends -bifury `cated to .,dene a notch .49 engageable with one end -of the lifting lever 4Q. An L.sh'aped.slot 53 perforates 4latching plate 52. Slot 53 encompasses a headed pin 54 which sis vfirmly anchored in a rectangular boss 50 ofhub 32 vand which slidablyholds ,plate 52 against boss Sil. Advance- .ment and vretraction of the `shoe 37 is accomplished by sliding latching .plate SZ/along guide slot r53. When the leg ofthe L-Shaped slot 5 3 bears .in contact relation :to head ypin 54. When .in this position, llifting lever -.4)zis urged upwardly by the inner 4margin of notch-@and s aid lever is `caused topivotV about Vpin 42mV opposition tothe compressive force of spring 4.4. Under these conditions the threaded shoe 3 7 is retracted :from the lead screw 1 2 on shaft 2. Consequently, there is no interlocking or mechanical connection between hub 32 and lead screwll. Therefore, .when the late hingplateis in the position shown in Fig. `3, the hub is free to movelongitudinally along the taper sleeve 13.

It will be notedalso that when threaded shoe37 isretracted from lead screw 12 said shoe is still disposed within key.slot 14 of sleeve 13. Lf crank -34is revolved under these conditions aboutthe axis of shaftZ, the,shoe;37 `will ,engage A the sleeve 13 within-slot .14 `and the `cc )rnbination of hub 32 and sleeve 13 will revolve freely on leadscrew 12. Y 4

A novel mechanism is provided for mechanically interlocking the hub 32 with the shaft 2. Attention is directed to Figs. 1 and'4. These figures shou a locking plate 2t) which comprises a cylindrical member Lhaving across its innerface agroove 21. Groove 21 is engageable with lugs 33protruding from the face of hub 32. Groove 21 of locking plate 20 also receives a flattened tongued end v portion 16 of shaft 2. When the tongued end portion 16 and lugs 33 are simultaneously received by groove 21, the hub 32 and shaft 2 are mechanically interlocked.

Locking plate l20 has a hole 28 coincidental with its axis for revolving on a screw 22 which has a threaded vportion 23 screwed into the end of shaft 2. Locking plate20 is permitted torevolve on screw 22 but is retained'against sliding thereon by a retaining pin 25 which extends'into annular Vgroove 24 which is cut in the outer periphery of yscrew 22. Screw 22 has its end portion 26 serrated for tightly receiving a knob 27. Rotation of screw 22 by means of knob 27 to withdrawit from the shaft causes groove 21 of Vlocking plate 20 to be backed lclear of lug 33 and tongue 16, so that the hub 32 and shaft 2 are notmechanically connected. A

`An alternative form of mechanism for interlocking hub 32'and shaft 2Vis shown in Figs. 5 and 6. To substitute this locking mechanism in place of locking plate 20 and the tongue and groove arrangement heretofore described, it is necessary to turn shaft 2 to a diameter at its end equal to the `diameter of the `lead screw 12. A hole 70 is then drilled radially into shaft 2 and adapted to receive a lockingkpin 71. Pin 71 is advanceable and retractable into hole70 by virtue of it being carried'pivotally on a lever 40 identical to the lever 40 which carries shoe 37. The lever 40` may be biased by a spring 44 and positioned by a latching plate 52 in a manner similar to the means shown for moving and positioning the shoe 37. v The purposepof this locking means is identical to that of the lock- 'ing plate assembly and its mode of operation is selfevident. p

A hand crank 34 is preferably cast integral with hub 32 and is provided with a rib 60 substantially disposed parallel to the longitudinal axis of shaft 2. Rib 60 has slot 4 it will benoted that hub 32 is restrained from sliding movement upon sleeve 13. It is to be further noted'that when locking plate 20,Y lugs 33 and tongued end portion 16 are engaged, the hub 32 is directly and rigidly mechanically connected to shaft 2. Upon rotation of crank 34, shaft 2 will rotate and threaded portion 3thereof will urge the collar 5 toward its mating collar 5a. When this occurs, the flanges 6 of collars Sand 5a will exert a sidewise force on the rubber ring 7. Collar 5a, though it is freely and slidably carried on shaft 2, will not slide longitudinally thereon because Vits face 6a butts the end portionl 17 of sleeve 13. Sleeve 13, of course, may not slide upon the lead `screw 12 because it thrusts against snap ring 18 near the end of shaft 2. Consequently, when shaft 2 is turned as ldescribed, the compressive force generated by the bearing relation of flange 6 on ring 7 is transmitted to the rubber ring on collar Sa by means of a solid cylindrical member 3 interposed between and lbearing upon said rubber ring. A radial expansion of rubber Yrings 7 is thereby effected and rings 7 are caused to tightly grip the interior wallsof ber conduit pipe 1.

` Attention. is directed toFig.-l where the solid lines indicate they position of the cutting bit 63 at the commencement of the taper cutting operation. It is to be noted that' the cutting bit63V bears againstthe end of conduit 1. This position may be attained by pushing the y tion in Fig. 3'so'that the end portion 55 of the L-shaped slot 53 in latching plate 52 approaches headed pin 54.

` Before proceeding with the taper cutting operation, the

62 cut therein radially relative to the axis of shaft 2 for i receiving cutting tool bit 63 and end facing bit 64. These bits are restrained against radial movement outward from the axis of shaft 2 by means of a clamping plate 65 which has clearance holes 67 through its face. These clearance holes freely receive adjusting screws 66 which have a threaded portion 68 screwed into the rib 60 of crank 34.

When these screws are turned down'so that their heads bear against clamping plate 65, the clamping plate in turn thereby securing the bits tightly within slot 62.

The use and operation of my invention is as follows: When it is desired to cut a taper on the end portion of a ber pipe 1 such as is illustrated in Fig. 1, the mandrel assembly is inserted within the pipe 1. During thisv operation, the rubber rings 7 carried by the collars 5 andv 5a are in loose concentric contact relation to the interior walls of pipe 1. While the entire mandrel assembly is resting `within pipe 1, the operator may turn screw 28 into the is then tripped sidewise to dispose the headed pin 54 in registry with vertical portion of the slot 53 and'is then moved vertically until the pin is positioned at the lower end 55 of the slot. Under these conditions, spring 44 'bears in high pressure relation to tool bits 63 and 64, f

urges lever 40 to pivot about iixed pin 42 and to bias the shoe 37 upwardly to engage it with the lead screw 12 of shaft 2.V When the shoe 37 is engaged with lea'd screw 12,

` locking plate is movedy outwardly to disengagethe lug 33 of hub 32 and the tongued end portion 16 of shaft 2 from the groove 21 in locking plate 20 as previously described. With thethreaded face 37a of shoe 37 in engagement with lead screw 12 of shaft'2, the crank 34 may be manually revolved about the axis of shaft 2. Shoe 37, being connected to hub 32, carries hub 32 longitudinally with it and slidably Valong the outer periphery of sleeve 13. The movement of cutting bit 63 will duplicate the helical movement of thel shoe 37 as it follows its helical path aboutV the lead screw 12. It will be observed that shoe 37 fits freelyin key slot 14 of hub 32. Consequently, upon rotation of crank 34, sleeve 13 is also caused to rotate on lead screw 12. Simultaneously, hub 32 is caused to slide axially upon the outer periphery of sleeve 13. The angle of the tapered surface generated on the pipe 1 relative to the axis of the pipe-is the same as the angle of the periphery of the sleeve 13 is tothe axis of'shaft 2.

kWhen the desired taper has been cut on the end of liber pipe 1, the end facingcutting bit 64 is adjacent the end Vof'pipeV 1. Cutting bit 64 may have its cutting edge ground at any desired angle toy conform it to the chamfer desired at the end of the pipe.

I fAfterthetaper cutting operation has been completed,

`removal,V of the'mandrel assembly is a relatively simple operation. VIt'is only necessary to back the hub 32 against the locking plate'20 by simply retracting shoe 37 to disengaged position relative to lead screw 12 of shaft 2 and then slide hub'32 upon sleeve 13 to its stop position against locking plate 20. Shoe 37 is then allowed to advance to threaded engagement withl lead screw 12, and screw 2S is turned clockwise to bring locking plate 20 into engagement with lugs 33 and tongued end 16 of shaft 2. This latter .operation brings the crank 34 into rigid mechanicalconnection with shaft 2. Now a few additional counterclockwise turns of shaft 2 cause thread 3 to back out of holek 4, thereby allowing collar 5 to proceed inn wardly ofthe pipe. When this `takes place, the resilient force of vrubber ring f7 tends to cause them to expand longitudinally and to contract radially, thereby reducing theoutsride diameter of ring 7 and freeing the outer periphery of said ring from contact engagement with the interior :walls of pipe 1'. Now the taper cutting tool can be removed from the pipe upon whichthe taperhas been cut by manually removing it from-the pipe. j

Attention is directed to several additional advantages which are inherent in the described tapering tool but not readily apparent to one who has not actually used the tool to cut a taper on a pipe. l

. It is to be appreciated that the toolisvcapableof exerting sufficient force on the interior of a fiberpipe, upon which a taper is to be cut, toforin the wall of the'` pipe into a lperfect circle concentric with the mandrel collars. Hence, though the cross section of a liber pipe may be elliptical prior to insertion of the tapering tool within its bore, the tool will restore the concentricity "to the pipe thereby assuring that fa taper'of equal depth will be cut about `the periphery of the pipe end. Removal of the tapering tool from the pipe will permit it to resume its elliptical shape but, novharrn results because circularity of the tapered end is restored when it is ultimately driven into a fitting or another pipe having a circular hole.

In addition, the use of soft resilient rubber rings to engage the interior of the pipe enables the development of secure frictional engagement between the mandrel and i fiber pipe without impressing or scoring its interior surface and without danger of fracturing it. If the inside diameter of a particular piece of` pipe happens to be slightly undersize, the resilient rings will not expand radially unlimited when the mandrel is tightened but will ow or 'yield longitudinally to relieve the radial stress. This feature will inherently prevent fracture of the pipe but, of course, one skilled in the art will recognize that very little tightening of the mandrel is needed to secure it within the pipe.

A final advantage lies in the tapering tool requiring very little effort to operate by reason of the mechanical advantage incidental to the use of a fairly long crank lever in` combination with a lead screw of small thread pitch. Hence, an operator can easily exert sutlicient effortto turn the crank orbitally to cut a fine, smooth taper without the necessity of the operator exerting any force in the direction of the cut to develop longitudinal feed.

It is claimed:

l. A tool for tapering an end of a cylindrical pipe comprising a shaft having a threaded end, clamping means adjacent said threaded end expansible radially into engagement with the inner periphery of said pipe, a lead screw at the other end of said shaft, a sleeve journaled on said lead screw and having the axis of its outer periphery inclined to the axis of said shaft, said sleeve having a slot through its wall extending in the direction of the shaft axis, a hub slidable on said sleeve, a shoe having a threaded face disposed within said key slot and threadedly engageable with said lead screw, shoe positioning means carried by the hub and carrying said shoe for advancing and retracting said threaded face into and out of engagement with the lead screw, cutting tool means rotatable with said hub, whereby rotation of said hub when said threaded face and lead screw are engaged will urge said hub along said sleeve at an angle with respect to the axis of said shaft and said pipe.

`2. A tool for tapering the end of a cylindrical pipe comprising a shaft'having one end for extending into a pipe, expansible means carried on said one end for compressively engaging a pipe interior in response to rotation of Said shaft, a sleeve journalled on the other end of said shaft and securedagainst sliding toward said one end, said sleeve having the, axis of its outer periphery inclined to the axis of said shaft and having a longitudinally disposed keyslot therein, a driving member slidably carried on said sleeve, means carried by said driving member and extending into said keyslot for interconnecting said driving member and sleeve whereby said driving member may slide longitudinally of the sleeve in fixed angular relation therewith, and a cutting bit supported by said driving member, said cutting bit tracing a cone of revolution when said rotatable member is rotated with and axially advanced on said-sleeve. l

3. In a tool for tapering the end of a cylindrical `pipe which includes an expansible mandrel operable into gripping relation with the interior of said pipe by means of rotating a threaded shaft; a shaft connected to said mandrel at one end and having a tongue projecting from its other end, a lead screw on said shaft adjacent 'said tongue, a sleeve journaled on said lead screw, a hub having a lug projecting in the direction of said tongue, said hub being slidable on said sleeve and rotatable therewith,v a locking plate having a groove `for receiving said lug and tongue simultaneously, screw means carrying said locking plate and operable to `urge said groove into registry with said lug and tongue, and cutting tool means mounted on said hub for advancement along said sleeve.

4. A tool for tapering an end of a cylindrical pipe comprising a shaft having a threadedportion at one end and a radial hole at the other end, clamping means at said one end of said shaft expansible radially into engagement with the inner periphery of said pipe, a lead screw at the other end of said shaft, a sleeve journaled on said lead c screw and having a key slot through its wall extending longitudinally parallel to the axis of said shaft, a hub slidable longitudinally on said sleeve, threaded shoe means carried by said hub engageable with said lead screw within said key slot, a lever pivotally carried by said hub, a locking pin pivotally carried by said lever, said pin being advanceable and retractable relative to said radial hole in said shaft, a latching plate carried by said hub and engageable with said lever for selectively inserting and withdrawing said locking pin relative to said shaft.

5. A tool for tapering an end of a cylindrical pipe comprising a shaft having a threaded portion at one end, a first collar threadedly engaged with and concentrically related to said threaded portion, a second collar on said shaft axially spaced from the first collar and retained against sliding movement relative thereto, said collars each having a radial ange on an end most remote from the other collar, a resilient ring circumjacent to each of said collars and expansible radially into engagement with the inner periphery of said pipe, said resilient ring having an outside diameter greater than the outside diameter of said flanges whereby excessive radial pressure on said rings may be relieved by longitudinal yielding thereof relative to said collars, cylindrical spacing means mounted on said collars having a diameter less than the outside diameter of said resilient rings and interposed between said rings in bearing relation therewith, a hub rotatable about the other end of said shaft, releasable means for interlocking said hub and said shaft whereby said shaft may be rotated relative to said collars and thereby move said collars relative to each other axially of said shaft.

6. A tool for tapering an end of a cylindrical pipe comprising a shaft having a threaded portion at one end, clamping means at one end of said shaft expansible radially into engagement with the inner periphery of said pipe, a lead screw at the other end of said shaft, a sleeve journaled on said lead screw and having the axis of its outer periphery inclined to the axis of said shaft, said sleeve having a key slot through its wall extending longitudinally parallel to the axis of said shaft, a hub slidable longitudinally on said sleeve, a shoe having a threaded face disposed within said key slot and threadedly engageable with said lead screw, lever means pivotally mounted intermediate its ends on said hub and carrying said shoe, spring means interposed between said hub and said lever biasing said shoe into threaded engagement with said lead screw, a latching plate adjacent said hub and having a slot therethrough, pin means encompassed by said slot for positioning said latching plate relative to said hub,

bifurcated ends on said latching plate for receiving and holding said lever means in opposition to said spring, and releasable means for interlocking said shaft and said hub.

7, A tool for tapering an end of a cylindrical pipe comprising a shaft having a threaded portion at one end, a rst collar threadedly engaged with and concentrically related to said threaded portion, a second collar on said shaftY axially spaced from the rst collar and retained against sliding movement relative thereto, a resilient ring circumjacent to each of said collars and expansible radially into engagement with the inner periphery of said pipe, a cylindrical spacer interposed between said rings and bearing thereagainst, a lead screw at the other end of said shaft, a sleeve journaled on said lead screw and having the aXis of its outer periphery inclined to the axis of the shaft, said sleeve having a key slot through its wall extending longitudinally parallel to the axis of said shaft, a hub slidable longitudinally on said sleeve and having alug projecting from one end, a shoe having a threaded face disposed within said key slot and engageable with said lead screw, lever means pivotally mounted intermediate its ends on said hub and pivotally carrying said shoe, spring means interposed between said hub and said lever means biasing said shoe into threaded engagement with said lead screw, a latching plate adjacent said hub and having an L-shaped slot therethrough, pin means encompassed by` said slot for'positioning said latching plate relative to said hub, a tongued end on said shaft, a locking plate adjacent said tongued end and having a groove for simultaneously receiving said lug and said tongued end, and screw means revolubly carrying said locking plate for advancing and retracting said locking plate.

References Cited in the le of this patent I UNITED STATES PATENTS Larson July 14, 1953 

